target-ppc: fix SPE evcmp* instructions

target-ppc: fix SPE evcmp* instructions

The CRF_{CH,CL,CH_OR_CL,CH_AND_CL} constants were all off by one bit
position.  Because of this, the SPE evcmp* family of instructions would
store values in the result condition register that were also off by one
bit position.

Fixed by using the CRF_{LT,GT,EQ,SO} constants for the shift amounts.

Signed-off-by: Nathan Froyd <froydnj@codesourcery.com>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>